CN112088138A

CN112088138A - Safety device for elevator and safety system for elevator

Info

Publication number: CN112088138A
Application number: CN201880093222.9A
Authority: CN
Inventors: 粉川靖之
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2018-05-14
Filing date: 2018-05-14
Publication date: 2020-12-15
Anticipated expiration: 2038-05-14
Also published as: CN112088138B; DE112018007600T5; WO2019220505A1; JP6854974B2; JPWO2019220505A1

Abstract

In the safety device of the elevator, the driving elastic body generates a rotating force which enables the driving axial braking component to rotate in the direction of contacting with the guide rail. The stopper lever is displaced between a restricting position where the stopper lever receives the drive lever and a release position where the stopper lever is disengaged from the drive lever by rotating about a stopper shaft provided to the vertically movable body. The actuator displaces the stopper rod from the restricting position to the releasing position by a releasing operation of the actuator. In a state where the drive lever is received by the stopper lever at the restriction position, a direction of a force acting on the stopper shaft from the drive lever via the stopper lever is a direction perpendicular to an imaginary plane including a contact portion of the stopper lever with the drive lever and an axis of the drive shaft.

Description

Safety device for elevator and safety system for elevator

Technical Field

The present invention relates to a safety device for an elevator and a safety system for an elevator, in which a braking member is brought into contact with a guide rail to apply a braking force to a lifting body.

Background

Conventionally, there is known an elevator safety device in which a governor rope is connected to a braking unit provided in a car, and when a traveling speed of the car exceeds an allowable speed, movement of the governor rope is stopped by a governor to pull up the governor rope relative to the car, so that a wedge of the braking unit is brought into contact with a guide rail to bring the car to an emergency stop.

However, in an elevator for a high-rise building, a governor rope pulled over the entire length of a hoistway may be caught by elevator equipment in the hoistway under the influence of building sway caused by a long-term earthquake, a strong wind, or the like. If the governor rope is caught by the elevator equipment, abnormal stopping of the car or damage to the elevator equipment may occur. Therefore, conventionally, a safety device for an elevator without a governor rope has been proposed.

For example, conventionally, there has been proposed a safety device for an elevator, in which when a traveling speed of a car exceeds an allowable speed, an actuator directly lifts a wedge by controlling power supply to the actuator, and the wedge is brought into contact with a guide rail (for example, see patent document 1).

Further, conventionally, there has been proposed a safety device for an elevator in which a link structure of a lock mechanism prevents rotation of a rotary shaft urged by an elastic force of a compression spring, and when a traveling speed of a car exceeds an allowable speed, power supply to an actuator is controlled to release restriction of rotation of the rotary shaft by the lock mechanism, thereby bringing a wedge into contact with a guide rail. The restriction of the rotation of the rotary shaft by the lock mechanism is released by the actuator operating the link structure of the lock mechanism against the elastic force of the compression spring (see, for example, patent document 2).

Documents of the prior art

Patent document

Patent document 1: japanese Kohyo publication 2007-521203

Patent document 2: japanese patent laid-open publication No. 2013-189283

Disclosure of Invention

Problems to be solved by the invention

However, in the conventional safety device for an elevator described in patent document 1, when the size of the car becomes large, the wedges become large along with an increase in the weight of the car, and therefore, it is necessary to increase the output of the actuator for lifting the wedges. Therefore, in the conventional safety device for an elevator described in patent document 1, the actuator is increased in size.

In addition, in the conventional safety device for an elevator described in patent document 2, since a plurality of link members need to be connected to form a link structure, the structure becomes complicated. In the conventional safety device for an elevator described in patent document 2, when the size of the car increases, the elastic force of the compression spring that rotates the rotary shaft increases, and therefore, it is necessary to increase the output of the actuator that releases the lock mechanism against the elastic force of the compression spring. Therefore, in the conventional safety device for an elevator described in patent document 2, the actuator is also increased in size.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an elevator safety device and an elevator safety system that can simplify the structure and suppress an increase in size.

Means for solving the problems

The safety device of an elevator and the safety system of an elevator of the invention are provided with: a drive shaft rotatably provided to a vertically movable body that moves along the guide rail; a brake mechanism unit having a brake member that is displaced relative to the vertically movable body in accordance with the rotation of the drive shaft, and applying a braking force to the vertically movable body by the contact of the brake member with the guide rail; a driving elastic body which generates a rotational force for rotating the driving shaft in a direction in which the braking member comes into contact with the guide rail; a drive lever that rotates integrally with the drive shaft; a stopper lever that is displaced between a restriction position where the stopper lever receives the drive lever and a release position where the stopper lever is disengaged from the drive lever by rotating about a stopper shaft provided to the lifting body; and an actuator having an actuator, wherein the actuator releases the actuator to displace the stopper rod from the limit position to the release position, the stopper rod receives the drive rod at the limit position to prevent the drive shaft from rotating in a direction in which the stopper member contacts the guide rail, and a direction of a force acting on the stopper shaft from the drive rod via the stopper rod in a state in which the stopper rod receives the drive rod at the limit position is a direction perpendicular to an imaginary plane including a contact portion of the stopper rod with the drive rod and an axis of the drive shaft.

Effects of the invention

According to the elevator safety device and the elevator safety system of the present invention, the stopper rod can be displaced from the restricting position to the releasing position without overcoming the rotational force of the drive elastic body acting on the drive rod. This can suppress an increase in size of the operation device for displacing the stopper rod from the restricting position to the releasing position, and can suppress an increase in size of the safety device of the elevator. Further, the rotation of the drive shaft due to the rotational force of the drive elastic body can be prevented with a simple structure. This can simplify the structure of the safety device of the elevator.

Drawings

Fig. 1 is a front view showing an elevator including an elevator safety device according to embodiment 1 of the present invention.

Fig. 2 is a partially cut-away perspective view illustrating the driving-side brake unit of fig. 1.

Fig. 3 is a sectional view taken along the line III-III of fig. 1.

Fig. 4 is a side view illustrating the driving-side brake unit of fig. 2.

Fig. 5 is a side view showing a state in which the driving-side brake unit of fig. 4 applies a braking force to the car.

Fig. 6 is a sectional view taken along line VI-VI of fig. 1.

Fig. 7 is an enlarged view illustrating the safety device of fig. 1.

Fig. 8 is a flowchart showing control of the elevator of fig. 1.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1.

Fig. 1 is a front view showing an elevator including an elevator safety device according to embodiment 1 of the present invention. In the figure, a hoistway is provided with a pair of

car guide rails

1a and 1b and a pair of counterweight guide rails, not shown. The pair of

car guide rails

1a and 1b and the pair of counterweight guide rails are arranged in the vertical direction. A car 2 as an elevating body is disposed between the pair of

car guide rails

1a and 1 b. A counterweight as a lifting body is disposed between a pair of counterweight guide rails. The car 2 and the counterweight are suspended by the main rope 3. The main ropes 3 use ropes or belts. The main ropes 3 are wound around a drive sheave of a hoisting machine, not shown, installed in the hoistway. The car 2 moves in the vertical direction along each of the pair of

car guide rails

1a and 1b by rotation of the drive sheave of the hoisting machine. The counterweight is moved in the up-down direction along each of a pair of counterweight guide rails by rotation of a drive sheave of the hoisting machine.

The car 2 includes a car body 21 and a car frame 22 supporting the car body 21. The car frame 22 has: an upper frame 221 located above the car body 21; a lower frame 222 located below the car body 21; and a pair of uprights 223 connecting the upper frame 221 and the lower frame 222, respectively. The main rope 3 is connected to the upper frame 221. The car body 21 is supported by the car frame 22 in a state of being placed on the lower frame 222.

The lower frame 222 is provided with an elevator safety device 4 capable of applying a braking force to the car 2. The upper frame 221 is provided with a sensor 5 that detects the position and speed of the car 2. The sensor 5 may also be arranged in any part of the car 2. For example, the sensor 5 may be provided at a lower portion of the car 2. As the sensor 5, for example, a sensor that generates a signal corresponding to rotation of a roller that comes into contact with one of the pair of

car guide rails

1a, 1b, or a sensor that detects a plurality of marks that are attached to one of the pair of

car guide rails

1a, 1b at intervals in the moving direction of the car 2 is used.

The information on the position and speed of the car 2 detected by the sensor 5 is sent to a control 6 which controls the operation of the elevator. The control device 6 controls the operation of the safety device 4 based on information from the sensor 5. In this example, the control device 6 is installed in the hoistway.

The lower frame 222 is horizontally arranged along the width direction of the car 2. The 1 st end 222a of the lower frame 222 faces one car guide rail 1 a. The 2 nd end 222b of the lower frame 222 is opposed to the other car guide rail 1 b. The safety device 4 has: a drive-side brake unit 7 provided at the 1 st end 222a of the lower frame 222; a driven-side brake unit 8 provided at the 2 nd end 222b of the lower frame 222; and a connecting rod 9 connected to the driving-side brake unit 7 and the driven-side brake unit 8. The operation of the driven-side brake unit 8 is interlocked with the operation of the driving-side brake unit 7 via the connecting rod 9.

Fig. 2 is a partially cut-away perspective view illustrating the driving-side brake unit 7 of fig. 1. Further, fig. 3 is a sectional view taken along the line III-III of fig. 1. The lower frame 222 includes a pair of lower frame beams 224 facing each other in the depth direction of the car 2. A flat plate 225 is fixed to the 1 st end 222a and the 2 nd end 222b of the lower frame 222, respectively. The flat plate 225 is horizontally disposed between the upper portions of the pair of lower frame beams 224.

The drive-side brake unit 7 includes: a drive shaft 10 provided rotatably to the lower frame 222; a brake mechanism 11 that can apply a braking force to the car 2 in conjunction with the rotation of the drive shaft 10; a torsion spring 12 which is a driving elastic body and generates a rotational force in a direction in which the drive shaft 10 applies a braking force to the car 2 to the brake mechanism 11; a drive lever 13 fixed to the drive shaft 10 and rotating integrally with the drive shaft 10; and a lock mechanism 14 that prevents the rotation of the drive shaft 10 by the rotational force of the torsion spring 12 and restricts the operation of the brake mechanism 11.

The drive shafts 10 are horizontally arranged in a state of penetrating the pair of lower frame members 224, respectively. In this example, the drive shaft 10 is disposed along the depth direction of the car 2. The drive shaft 10 rotates with respect to the lower frame 222 centering on the axis of the drive shaft 10.

The brake mechanism 11 is supported by the lower frame 222. The brake mechanism 11 is disposed below the flat plate 225 and between the pair of lower frame beams 224. That is, the brake mechanism 11 is disposed in a space surrounded by the flat plate 225 and the pair of lower frame beams 224. Further, the brake mechanism 11 includes: a pair of clamping members 111 having a rail-side end and a rail-opposite end; a pair of wedges 112 disposed between the rail-side ends of the pair of gripping members 111, respectively, as a pair of braking members; and a pressing spring 113, which is disposed between the opposite ends of the guide rail of each of the pair of clamping members 111, and serves as a pressing elastic body.

The intermediate portions of the pair of clamping members 111 are coupled to each other by a common coupling shaft extending in the vertical direction. The pair of clamping members 111 can be displaced from each other about a common connecting shaft. The distance between the rail opposite side ends of the pair of gripping members 111 becomes larger as the distance between the rail side ends of the pair of gripping members 111 becomes smaller, and becomes smaller as the distance between the rail side ends of the pair of gripping members 111 becomes larger.

As shown in fig. 3, the guide rail side end portions of the pair of gripping members 111 are located on both sides in the width direction of one car guide rail 1 a. The gap between each of the rail-side end portions of the gripping members 111 and the side surface of the car guide rail 1a is continuously narrowed from the lower portion to the upper portion of the gripping members 111.

As shown in fig. 3, the pair of wedges 112 are respectively disposed between each of the guide rail side end portions of the pair of gripping members 111 and one of the car guide rails 1 a. The pair of wedges 112 are coupled to the drive shaft 10 via link members 114. Each link member 114 is fixed to the drive shaft 10. Thereby, the pair of wedges 112 are displaced in the up-down direction with respect to the car 2 in accordance with the rotation of the drive shaft 10. The pair of wedges 112 are respectively displaced upward relative to the car 2 from a normal position shown in fig. 3 separated from the one car guide rail 1a, and are thereby guided by the guide rail side end portions of the gripping members 111 in a direction of contacting the car guide rail 1 a. The wedges 112 are brought into contact with the car guide rail 1a to apply a braking force to the car 2.

When the wedges 112 come into contact with the car guide rails 1a when the car 2 descends, the wedges 112 are displaced further upward with respect to the car 2 while expanding the gap between the guide rail side end portion of the gripping member 111 and the car guide rails 1 a. Thereby, each wedge 112 is engaged between the guide rail side end of the holding member 111 and the car guide rail 1 a.

As shown in fig. 2, the pressing spring 113 is disposed between the rail-opposite-side end portions of the pair of gripping members 111. Therefore, the gap between the guide rail side end portion of the clamp member 111 and the car guide rail 1a is widened by the wedge 112, and the pressing spring 113 generates an elastic restoring force in a direction of pressing the wedge 112 to the car guide rail 1 a. In the braking mechanism 11, the pair of wedges 112 are pressed against the car guide rail 1a by the elastic restoring force of the pressing spring 113, respectively, thereby securing braking force for stopping the car 2.

A torsion spring 12 is provided at one end of the drive shaft 10. In this example, the drive shaft 10 is inserted inside the torsion spring 12. One end of the torsion spring 12 is connected to the drive shaft 10, and the other end of the torsion spring 12 is connected to the lower frame beam 224. The torsion spring 12 generates a rotational force by elastic deformation, and the rotational force rotates the drive shaft 10 in a direction in which each wedge 112 moves upward with respect to the car 2 from the normal position of fig. 3, that is, in a direction in which each wedge 112 contacts the car guide rail 1 a.

A drive lever 13 is provided at the other end portion of the drive shaft 10. The drive lever 13 rotates integrally with the drive shaft 10 around the axis of the drive shaft 10. The drive lever 13 includes a plate-like lever main body 131 fixed to the drive shaft 10, and a cam follower 132 as a projection projecting from the lever main body 131.

The lever main body 131 is fixed to the drive shaft 10 in a state perpendicular to the axis of the drive shaft 10. The cam follower 132 protrudes from the lever main body 131 in parallel with the axis of the drive shaft 10 at a position apart from the drive shaft 10. In this example, a roller that can rotate about an axis protruding from the lever main body 131 is provided as the cam follower 132 in the lever main body 131. Further, a columnar wear-resistant member fixed to the lever main body 131 may be used as the cam follower 132.

Fig. 4 is a side view showing the drive-side brake unit 7 of fig. 2. Fig. 5 is a side view showing a state in which the driving-side brake unit 7 of fig. 4 applies a braking force to the car 2. The lock mechanism 14 includes: a stopper lever 142 that is rotatable about an axis P1 of a stopper shaft 141 of a lower frame beam 224 provided on a lower frame 222; and an actuator 143 that rotates the stopper rod 142 about the stopper shaft 141 under the control of the controller 6.

The stopper shaft 141 is disposed parallel to the drive shaft 10. The stopper shaft 141 is disposed above the cam follower 132. When the drive shaft 10 rotates in a direction in which the wedge 112 contacts the car guide rail 1a from the normal position, the drive lever 13 rotates in a direction in which the cam follower 132 approaches the stopper shaft 141. That is, when the drive shaft 10 rotates in a direction to lift up the wedge 112 as shown by arrow C in fig. 5, the drive lever 13 rotates in a direction of arrow B in fig. 5. A rotational force is applied to the drive lever 13 in a direction in which the cam follower 132 approaches the stopper shaft 141 by the torsion spring 12.

The stopper lever 142 is displaced between the restricting position of fig. 4 receiving the cam follower 132 and the release position of fig. 5 disengaged from the cam follower 132 by rotating about the axis P1 of the stopper shaft 141.

As shown in fig. 4, the stopper rod 142 receives the cam follower 132 of the drive lever 13 at the restricting position, and thereby prevents the drive shaft 10 from rotating in a direction in which each wedge 112 contacts the car guide rail 1a, that is, in a direction of an arrow B in fig. 5. Further, the stopper lever 142 allows the drive shaft 10 to rotate in a direction in which each wedge 112 contacts the car guide rail 1a by being disengaged from the cam follower 132 of the drive lever 13.

Further, the stopper lever 142 has: a boss 144 which is rotatably provided on the stopper shaft 141 and has a cylindrical shape; and a receiving portion 145 and a projecting portion 146 that project from the outer peripheral portion of the boss portion 144 toward the radially outer side of the boss portion 144. The receiving portion 145 and the projecting portion 146 project from different circumferential positions of the outer circumferential portion of the hub portion 144 from each other. In this example, the protruding length of the receiving portion 145 is longer than the protruding length of the protrusion portion 146.

As shown in fig. 4, the receiving portion 145 is a rod-shaped portion having a center line D1 perpendicular to the axis P1 of the stopper shaft 141. In this example, the shape of the receiving portion 145 as viewed from the outside of the drive-side brake unit 7 along the axis P1 of the stopper shaft 141 is symmetrical with respect to the center line D1 of the receiving portion 145. That is, in this example, the shape of the receiving portion 145 as viewed in the direction of the axis P1 is symmetrical about the center line D1 of the receiving portion 145.

The end surface 147 of the receiving portion 145 is a curved surface that contacts an imaginary circle centered on the axis P1 of the stopper shaft 141 when viewed from the outside of the drive side brake unit 7 along the axis P1 of the stopper shaft 141, that is, when viewed in the direction of the axis P1. The end surface 147 of the receiving portion 145 is located inside the imaginary circle in contact with the end surface 147. In this example, the shape of the end surface 147 when viewed from the outside of the drive-side brake unit 7 along the axis P1 of the stopper shaft 141, that is, the shape of the end surface 147 when viewed in the direction of the axis P1 is arc-shaped. The stopper rod 142 is provided on the stopper shaft 141 such that an end surface 147 of the receiving portion 145 faces downward.

In a state where the stopper lever 142 receives the cam follower 132 at the restricting position, as shown in fig. 4, the end surface 147 of the receiving portion 145 contacts the outer peripheral surface of the cam follower 132. In this example, the stopper rod 142 receives the cam follower 132 at the restricting position, and the end surface 147 of the receiving portion 145 and the cam follower 132 are brought into a line contact state. Therefore, in this example, the contact portion 145a of the receiving portion 145, which contacts the cam follower 132, is a linear contact portion parallel to the axis P1 of the stopper shaft 141. The curved surface of the end surface 147 of the receiving portion 145 may be in a point contact state with respect to the cam follower 132.

When the stopper lever 142 is viewed along the axis P1 of the stopper shaft 141, that is, viewed in the direction of the axis P1, a straight line connecting the contact portion 145a of the receiving portion 145, which is in contact with the cam follower 132, and the axis P1 of the stopper shaft 141 coincides with the center line D1 of the receiving portion 145. In a state where the stopper lever 142 receives the cam follower 132 of the drive lever 13 at the restriction position, the direction along the center line D1 of the receiving portion 145 coincides with the gravity direction, that is, the vertical direction. That is, in a state where the stopper lever 142 receives the drive lever 13 at the restriction position, the axis P1 of the stopper shaft 141 coincides with a vertical line passing through the contact portion 145a of the stopper lever 142 that contacts the drive lever 13.

In a state where the stopper lever 142 receives the cam follower 132 of the drive lever 13 at the restriction position, the direction of the force F acting on the stopper shaft 141 from the drive lever 13 via the stopper lever 142 is perpendicular to a virtual plane D2, and the virtual plane D2 includes the contact portion 145a of the receiving portion 145 that contacts the cam follower 132 and the axis P2 of the drive shaft 10. When viewed from the outside of the drive-side brake unit 7 along the axis P2 of the drive shaft 10, i.e., in the direction of the axis P2, the imaginary plane D2 can be seen as a straight line connecting the contact portion 145a and the axis P2 of the drive shaft 10. Therefore, in a state where the stopper lever 142 receives the cam follower 132 of the drive lever 13 at the restriction position, when the drive lever 13 and the stopper lever 142 are viewed from the outside of the drive-side brake unit 7 along the axis P2 of the drive shaft 10 and the axis P1 of the stopper shaft 141, as shown in fig. 4, the straight line D1 connecting the contact portion 145a and the axis P1 of the stopper shaft 141 is perpendicular to the straight line D2 connecting the contact portion 145a and the axis P2 of the drive shaft 10. That is, in a state where the stopper lever 142 receives the cam follower 132 at the restriction position, when viewed in the direction of the axis P1, the straight line D1 connecting the contact portion 145a and the axis P1 is perpendicular to the straight line D2 connecting the contact portion 145a and the axis P2.

The stopper rod 142 is displaced from the restricting position to the releasing position by rotating about the axis P1 of the stopper shaft 141 in the direction of arrow a in fig. 5, that is, in the direction in which the receiving portion 145 moves away from the drive shaft 10.

The projection 146 is provided on the opposite side of the stopper shaft 141 from the receiving portion 145. Further, when the stopper lever 142 is viewed along the axis P1 of the stopper shaft 141, that is, when viewed in the direction of the axis P1, the protrusion 146 is provided at a position deviated from the center line D1 of the receiving portion 145. Thus, in this example, the overall shape of the stopper rod 142 when viewed from the outside of the drive-side brake unit 7 along the axis P1 of the stopper shaft 141, that is, the overall shape of the stopper rod 142 when viewed in the direction of the axis P1, is asymmetrical with respect to the center line D1 of the receiver 145.

As shown in fig. 2, the lower frame beam 224 is provided with a lever receiving member 15, and the lever receiving member 15 prevents the stopper lever 142 from being displaced in a direction away from the restricting position. The stopper lever 142 is held at the release position in a state of hitting the lever receiving member 15.

As shown in fig. 4 and 5, the actuator 143 includes: an extension spring 16 serving as a release elastic body for urging the stopper lever 142 toward the release position; and an actuator 17 capable of holding the stopper lever 142 in the restricting position against the urging force of the extension spring 16.

The tension spring 16 is connected to the receiving portion 145 and the lower frame beam 224. Further, the tension spring 16 is elastically stretched between the receiving portion 145 and the lower frame beam 224. Thereby, the tension spring 16 generates an elastic restoring force that biases the stopper lever 142 to the release position. As the releasing elastic body for biasing the stopper lever 142 toward the releasing position, a torsion spring provided on the stopper shaft 141 may be used.

The actuator 17 is disposed on the side opposite to the tension spring 16 side with respect to the stopper lever 142 when viewed from the outside of the drive side brake unit 7 along the axis P1 of the stopper shaft 141, i.e., when viewed in the direction of the axis P1. Further, the actuator 17 has: an actuator body 171 including an electromagnetic coil; and a lever 172 that is a movable portion that is displaceable between an advanced position and a retracted position with respect to the actuator main body 171.

The actuator main body 171 is fixed to the lower frame beam 224. The electromagnetic coil of the actuator main body 171 can be supplied with power by the control of the control device 6. The actuator main body 171 generates an electromagnetic force that displaces the rod 172 from the reverse position to the forward position by supplying electricity to the electromagnetic coil. Further, by stopping the supply of electric power to the electromagnetic coil, the actuator main body 171 stops generating the electromagnetic force to the rod 172.

The lever 172 has a lever protrusion 172a protruding from the actuator main body 171. The length of the lever protrusion 172a is increased by the lever 172 being displaced from the retracted position to the advanced position.

Further, the lever 172 is displaced relative to the actuator main body 171 between the forward position and the backward position by controlling the supply of power to the actuator main body 171 by the control device 6. The displacement of the rod 172 with respect to the actuator main body 171 is restricted by a not-shown restricting portion of the actuator main body 171 so as not to go too far outward from the range between the forward position and the backward position.

By supplying power to the actuator main body 171, the rod 172 is displaced to the advanced position. In a state where the power supply to the actuator main body 171 is maintained, the lever 172 is held at the advanced position. The lever 172 in the advanced position receives the projection 146 via the lever projection 172 a. In the state where the lever 172 is held at the advanced position, the stopper lever 142 is held at the restricting position against the elastic restoring force of the tension spring 16. That is, the actuator 17 holds the stopper rod 142 at the restricting position while maintaining the power supply to the actuator main body 171.

Further, by stopping the supply of power to the actuator main body 171, the state in which the rod 172 is held at the advanced position by the electromagnetic force of the actuator main body 171 is released. When the power supply to the actuator main body 171 is stopped, the rod 172 receives the elastic restoring force of the tension spring 16 from the projection 172a, and is displaced from the advanced position to the retracted position. The state in which the stopper lever 142 is held at the restricting position is released by the lever 172 being displaced to the retreating position. That is, when the power supply to the actuator main body 171 is stopped, the actuator 17 performs a releasing operation of releasing the holding of the stopper rod 142 by the elastic restoring force of the tension spring 16.

The control device 6 is preset with a set excessive speed corresponding to the position of the car 2. The control device 6 performs control to maintain power supply to the actuator main body 171 during normal operation when the speed of the car 2 is equal to or lower than a set excessive speed. In addition, the control device 6 performs control to stop the power supply to the actuator main body 171 when an abnormality occurs in which the speed of the car 2 exceeds a set excessive speed.

Fig. 6 is a sectional view taken along line VI-VI of fig. 1. The driven-side brake unit 8 includes: a driven shaft 30 provided rotatably to the lower frame 222; a brake mechanism portion 31 that is linked with the rotation of the driven shaft 30 and can apply a braking force to the car 2; and a driven lever 32 fixed to the driven shaft 30 and rotating integrally with the driven shaft 30. The torsion spring 12 and the lock mechanism portion 14 of the driving-side brake unit 7 are not provided in the driven-side brake unit 8.

The driven shaft 30 is disposed in parallel with the driving shaft 10 in a state of penetrating the pair of lower frame members 224, respectively. The driven shaft 30 rotates with respect to the lower frame 222 centering on the axis of the driven shaft 30.

The structure of the brake mechanism unit 31 is the same as that of the brake mechanism unit 11 of the drive-side brake unit 7. Therefore, in the braking mechanism portion 31, the pair of wedges 112 are displaced relative to the car 2 in accordance with the rotation of the driven shaft 30, respectively. The pair of wedges 112 in the braking mechanism 31 are respectively displaced upward relative to the car 2 from the normal position shown in fig. 6, which is separated from the other car guide rail 1b, and are thereby guided by the guide rail side end portions of the gripping members 111 in the direction of contacting the car guide rail 1 b. The wedges 112 of the braking mechanism 31 contact the car guide rail 1b to apply a braking force to the car 2.

The driven lever 32 is provided to the driven shaft 30. The driven lever 32 rotates integrally with the driven shaft 30 about the axis of the driven shaft 30. The driven lever 32 is a plate-shaped lever fixed to the driven shaft 30 in a state perpendicular to the axis of the driven shaft 30.

Fig. 7 is an enlarged view showing the safety device 4 of fig. 1. One end of the connecting rod 9 is rotatably attached to a drive rod 13 of the drive-side brake unit 7. The other end of the connecting rod 9 is rotatably attached to a driven lever 32 of the driven-side brake unit 8. Thereby, the driven lever 32 rotates integrally with the driven shaft 30 in accordance with the rotation of the driving lever 13. That is, the rotation of the driven shaft 30 and the driven lever 32 is linked with the rotation of the drive shaft 10 and the drive lever 13 via the coupling rod 9.

In the driving-side brake unit 7, when the driving shaft 10 and the driving lever 13 are rotated in a direction in which the pair of wedges 112 are brought into contact with the one car guide rail 1a, the driven shaft 30 and the driven lever 32 are also rotated in a direction in which the pair of wedges 112 are brought into contact with the other car guide rail 1b in the driven-side brake unit 8. The elevator safety system includes a safety device 4, a sensor 5, and a control device 6.

Next, the operation will be described. Fig. 8 is a flowchart showing control of the elevator of fig. 1. The speed of the car 2 is constantly monitored by the control device 6 during elevator operation. That is, during the operation of the elevator, it is always determined by the control device 6 whether or not the speed of the car 2 exceeds the set excessive speed corresponding to the position of the car 2, based on the position and speed of the car 2 detected by the sensor 5 (S1). When the speed of the car 2 is equal to or lower than the set excessive speed, the power supply to the actuator 17 is maintained by the control of the control device 6. When the power supply to the actuator 17 is maintained, as shown in fig. 4, the rotation of the drive shaft 10 due to the elastic restoring force of the torsion spring 12 is prevented by the locking mechanism portion 14, and the application of the braking force to the car 2 is released. Thereby, the elevator continues to operate normally.

When the speed of the car 2 exceeds the set excessive speed due to breakage of the main ropes 3 or the like, the power supply to the actuator 17 is stopped under the control of the control device 6 (S2).

When the power supply to the actuator 17 is stopped, as shown in fig. 5, the stopper rod 142 rotates in the direction of arrow a in fig. 5, and the lock mechanism 14 releases the restriction of the rotation of the drive shaft 10. When the restriction of the rotation of the drive shaft 10 is released, the drive shaft 10 and the drive lever 13 are rotated in the direction of arrow B in fig. 5 by the elastic restoring force of the torsion spring 12. At this time, the driven shaft 30 and the driven lever 32 rotate in conjunction with the rotation of the drive lever 13. Thereby, the wedges 112 of the driving-side brake unit 7 are lifted in the direction of the arrow C in fig. 5, and the wedges 112 of the driven-side brake unit 8 are also lifted. Thus, in the driving-side brake unit 7 and the driven-side brake unit 8, the wedges 112 come into contact with the

car guide rails

1a and 1 b. That is, when the power supply to the actuator 17 is stopped, the safety device 4 performs a braking operation of bringing each wedge 112 into contact with the

car guide rails

1a and 1b (S3). When the safety device 4 performs a braking operation, a braking force is applied to the car 2, and the movement of the car 2 is stopped.

In the safety device 4 for an elevator, a direction of a force acting on the stopper shaft 141 from the drive lever 13 via the stopper lever 142 is a direction perpendicular to a virtual plane D2, and the virtual plane D2 includes the contact portion 145a of the stopper lever 142, which is in contact with the drive lever 13, and the axis P2 of the drive shaft 10. Therefore, when the stopper lever 142 receives the drive lever 13 at the restriction position, the force acting on the stopper lever 142 from the drive lever 13 can be made hard to act in the rotational direction of the stopper lever 142. Further, by rotating the stopper lever 142 about the stopper shaft 141, the stopper lever 142 can be displaced from the restricting position to the releasing position without overcoming the rotational force of the torsion spring 12 acting on the drive lever 13. Thereby, the magnitude of the force to displace the stopper lever 142 can be set regardless of the magnitude of the rotational force of the torsion spring 12. Therefore, even if the car 2 becomes large, the size of the actuator 143 for displacing the stopper rod 142 from the restricting position to the releasing position can be suppressed from increasing, and the size of the safety device 4 can be suppressed from increasing. Further, since the stopper lever 142 is disengaged from the drive lever 13 by the displacement of the stopper lever 142 from the restricting position to the releasing position, it is not necessary to use a complicated link structure as in the conventional art. Therefore, the structure of the safety device 4 can be simplified, and the reliability of the braking operation of the safety device 4 can be improved. Further, even if the size of the car 2 changes, the size of the locking mechanism portion 14 does not need to be changed, so that the parts of the safety device 4 of the elevator can be unified.

Further, in a state where the stopper lever 142 receives the drive lever 13 at the restriction position, the stopper lever 142 contacts the cam follower 132. Therefore, the stopper lever 142 can be more reliably and easily displaced from the restricting position to the releasing position.

In a state where the stopper lever 142 receives the drive lever 13 at the restriction position, a direction along a straight line D1 connecting a contact portion 145a of the stopper lever 142, which contacts the drive lever 13, and the axis P1 of the stopper shaft 141 is a vertical direction. Therefore, the inertial force acting on the stopper lever 142 due to the change in the speed of the car 2 can be made less likely to act in the circumferential direction of the stopper shaft 141. Accordingly, when the elevator is in normal operation, the occurrence of malfunction in which the detent lever 142 is displaced from the restricting position to the releasing position by the inertial force can be more reliably suppressed.

The releasing operation of the actuator 17 is performed by controlling the power supply to the actuator 17. Therefore, the actuator 17 having a small size and a simple structure can be used, and the governor rope pulled in the hoistway can be eliminated with a simple structure.

In the above example, the surface of the cam follower 132 with which the end surface 147 of the stopper rod 142 contacts is a cylindrical surface. However, the surface of the cam follower 132 with which the end surface 147 of the stopper lever 142 contacts is not limited to this, and may be a flat surface, for example.

Further, in the above example, the cam follower 132 with which the detent lever 142 is in contact protrudes from the lever main body 131. However, it is also possible to bring the stopper lever 142 into contact with the lever main body 131 from which the cam follower 132 is removed, so that the stopper lever 142 receives the drive lever 13. Even in this case, the direction of the force acting on the stopper shaft 141 from the drive lever 13 via the stopper lever 142 can be made perpendicular to the virtual plane D2, and the stopper lever 142 can be displaced from the restricting position to the releasing position without overcoming the rotational force of the torsion spring 12 acting on the drive lever 13.

In the above example, the axis P1 of the stopper shaft 141 is parallel to the axis P2 of the drive shaft 10. However, if the axis P1 of the stopper shaft 141 exists on another imaginary plane parallel to the imaginary plane D2, the axis P1 of the stopper shaft 141 may not be parallel to the axis P2 of the drive shaft 10. Even when the stopper lever 142 receives the drive lever 13 at the restricting position, the force acting on the stopper lever 142 from the drive lever 13 is made difficult to act in the rotational direction of the stopper lever 142, and the stopper lever 142 can be displaced from the restricting position to the release position without overcoming the rotational force of the torsion spring 12 acting on the drive lever 13.

In the above example, the actuator 143 includes the tension spring 16 and the actuator 17. However, the actuator 143 may not have the extension spring 16. For example, the actuator 17 may shift the stopper lever 142 from the restricting position to the releasing position by rotating the stopper lever 142 about the stopper shaft 141 while pressing the stopper lever 142 with the rod 172. In this case, a restricting member that receives the stopper lever 142 so that the stopper lever 142 does not shift from the restricting position to the direction opposite to the releasing position may be fixed to the lower frame rail 224.

In the above example, the overall shape of the stopper rod 142 when viewed from the outside of the drive-side brake unit 7 along the axis P1 of the stopper shaft 141, i.e., when viewed in the direction of the axis P1, is asymmetric with respect to the center line D1 of the receiver 145. However, the overall shape of the stopper rod 142 when viewed from the outside of the drive-side brake unit 7 along the axis P1 of the stopper shaft 141, i.e., when viewed in the direction of the axis P1, may be made symmetrical with respect to the center line D1 of the receiver 145. In this case, for example, the protrusion 146 protruding from the boss 144 of the stopper rod 142 may be disposed on the center line D1 of the receiving portion 145. In this case, by setting the direction along the center line D1 of the receiving portion 145 to the vertical direction, the inertial force acting on the stopper rod 142 due to the change in the speed of the car 2 can be made more reliably less likely to act in the circumferential direction of the stopper shaft 141. This can more reliably suppress the occurrence of malfunction of the safety device 4.

In the above example, the stopper bar 142 has a shape along the center line D1 as a whole. However, the shape of the stopper bar 142 is not limited thereto. For example, the stopper rod 142 may be shaped like a disc. In this case, the axis P1 of the stopper shaft 141 is disposed at an eccentric position that is offset from the center position of the disk shape of the stopper rod 142. In this case, the projection 146 received by the actuator 17 is provided on the outer peripheral portion of the circular plate of the stopper rod 142.

In the above example, when the drive lever 13 is received by the stopper lever 142 at the restriction position, the direction along the straight line D1 connecting the contact portion 145a and the axis P1 of the stopper shaft 141 is the vertical direction. However, the direction along the line D1 when the drive lever 13 is received at the restriction position of the stopper lever 142 may be inclined with respect to the vertical direction without coinciding with the vertical direction.

In the above example, the torsion spring 12 as the driving elastic body is provided only on the drive shaft 10 of the driving side brake unit 7 in the driving side brake unit 7 and the driven side brake unit 8. However, the torsion spring 12 may be provided on the drive shaft 10, and the torsion spring as the driving elastic body may be provided also on the driven shaft 30 of the driven-side brake unit 8.

In the above example, the torsion spring 12 is used as a driving elastic body for generating a rotational force for rotating the drive shaft 10. However, a spring other than the torsion spring 12 may be used as the driving elastic body. In this case, for example, a coil spring as a driving elastic body may be connected to a projection projecting radially outward from the drive shaft 10, and the coil spring may generate an elastic restoring force for rotating the drive shaft 10.

In the above example, the safety device 4 is provided in the car 2, but the safety device 4 may be provided in a counterweight as an ascending/descending body.

Description of the reference symbols

1a, 1 b: car guide rails (guide rails); 2: a car (lifting body); 4: a safety device; 5: a sensor; 6: a control device; 10: a drive shaft; 11: a brake mechanism section; 12: a torsion spring (elastic body for driving); 13: a drive rod; 17: an actuator; 112: a wedge (brake member); 131: a lever body; 132: a cam follower (protrusion); 141: a stop shaft; 142: a stopper rod; 143: an actuating device; 145 a: a contact portion.

Claims

1. A safety device for an elevator, comprising:

a drive shaft rotatably provided to a vertically movable body that moves along the guide rail;

a brake mechanism unit having a brake member that is displaced relative to the vertically movable body in accordance with rotation of the drive shaft, the brake member being in contact with the guide rail to apply a braking force to the vertically movable body;

a drive elastic body that generates a rotational force that rotates the drive shaft in a direction in which the brake member contacts the guide rail;

a drive lever that rotates integrally with the drive shaft;

a stopper lever that is displaced between a restricting position where the stopper lever receives the drive lever and a release position where the stopper lever is disengaged from the drive lever by rotating about a stopper shaft provided to the vertically movable body; and

an actuating device having an actuator, the detent lever being displaced from the restricting position to the releasing position by a releasing operation of the actuator,

the stopper rod prevents the drive shaft from rotating in a direction in which the brake member contacts the guide rail by receiving the drive rod at the restricting position,

in a state where the drive lever is received by the stopper lever at the restriction position, a direction of a force acting on the stopper shaft from the drive lever via the stopper lever is a direction perpendicular to an imaginary plane including a contact portion of the stopper lever with the drive lever and an axis of the drive shaft.

2. The safety device of an elevator according to claim 1,

the drive lever has: a lever main body fixed to the drive shaft; and a cam follower protruding from the lever main body at a position apart from the drive shaft,

the stopper lever is in contact with the cam follower in a state where the stopper lever receives the drive lever at the restricting position.

3. The safety device of an elevator according to claim 1 or 2,

in a state where the stopper lever receives the drive lever at the restriction position, an axis of the stopper shaft coincides with a vertical line passing through a contact portion of the stopper lever that contacts the drive lever.

4. The safety device of an elevator according to any one of claims 1 to 3,

the releasing operation of the actuator is performed by controlling power supply to the actuator.

5. A safety system for an elevator, comprising:

safety device of an elevator according to any of claims 1 to 4;

a sensor that detects a position and a speed of the elevating body; and

and a control device for controlling the actuator based on information on the position and speed of the lifting body detected by the sensor.